1. Field of the Invention
The invention relates to valve bags which are closed by pasting or sewing at both ends except for a filling valve in one corner, and more particularly to a type of bag which will lubricate the filling spout when it is inserted in the valve opening and facilitate slipping on the spout successive bags to be filled.
2. Description of the Prior Art
The prior art does not disclose a bag having the same construction as the bag of the present invention and which serves to lubricate the filling spout each time a bag is slipped on the spout to provide a lubricant for successive bags placed on the spout.
It is well known to apply a lubricant to spouts for filling bags, but such lubricant wears off rapidly and must be replaced. For example U.S. Pat. No. 3,294,127 discloses lubrication with a soap solution.
Other prior art patents disclose sheaths or cases to lubricate the product placed therein, i.e. U.S. Pat. Nos. 1,240,880; 1,612,861; 1,888,289; and 2,469,763. U.S. Pat. No. 3,282,414 discloses a prophylactic with lubricant. Other patents and publications disclose the use of Teflon as a lubricant, i.e. U.S. Pat. No. 3,080,183; British Pat. No. 770,774; and the "Journal of Teflon--Nov. 1965".